近年来,不少作者试验证实,固氮菌产生的生长调节物质刺激植物生长,从而提高植物干重。Barea等人(1974)用雀稗固氮菌(Azotobacter paspali)培养物处理几种植物苗、根,结果其根、叶重量显著增加。Tien等(1979)报导,植物接种产生三种植物激素的含脂固氮刚螺菌(Azospirillum brasilense)促进了根的生长。此外,Coppola等(1971)也从圆褐固氮菌(Azotobacter chroococcum)细胞浸 In recent years, many authors confirmed that nitrogen-fixing bacteria produce growth regulators to stimulate plant growth, thereby increasing plant dry weight. Barea et al. (1974) treated several plant shoots and roots with Azotobacter paspali cultures, resulting in a significant increase in root and leaf weight. Tien et al. (1979) reported that plant inoculation with Azospirillum brasilense, which produces three plant hormones, promotes root growth. In addition, Coppola et al. (1971) also dipped cells from Azotobacter chroococcum